Longshots Losing 98% of Time Dominate Kalshi, Polymarket Trading - Bloomberg. Carolyn Silverman and Denitsa Tsekova report that prediction markets tout themselves as “truth machines,” but trading data shows a lot of casino-like bets. Bettors flock to money-losing longshot wagers, making the sites look like a casino crossed with an arcade. Since early 2025, around half of all trading volume on Kalshi has involved one side chasing potential returns of at least 1,000%. On Polymarket International, longshots accounted for 52% of volume over the past 21 months.
Kalshi declined to comment; a Polymarket spokesperson noted longshot bettors' wagers are far smaller—about 1% of total volume—but that still amounted to more than $600 million in September alone across both platforms. For bettors taking those odds, losses pile up. On average, money staked on “yes” longshots lost 15% on Kalshi and 27% on Polymarket. Fees up to 7% swell losses further.
Philip Newall, a former poker player now at the University of Bristol, says the biggest puzzle is why people can't spot they're the sucker. Brian Cai, a former Meta Platforms Inc. employee, made longshot wagers alongside sober bets but realized how badly he was doing. A previous Bloomberg report found most Polymarket accounts lost money between January 2025 and April 2026.
Source: Bloomberg Markets · Summarized by HeadlinesBriefing